750 hydraulic clutch conversion?

Mine was okish one up, 2 up and it was POOR. That hydro was nuts, be interesting to see, the original one relied on one shoe tension from the inner and one shoe compression on the outer, how you equalised that was the issue that hydro would solve.
 
I’d suggest the only thing ‘comical’ about the Beezumph conical front drum, is the effort the ignorant put into covering up their inability to set up said brake properly.
Not as good as the previous twin leading drum of the Triumph/BSA group but not as bad as the reputation it’s been tarred with. IMO.
Oh, you mean it's similar to the Laverda drums? Setting these up seems to be wizardry/black magic for most...

Sorry, I've tried a few conicals and found them to be pretty pathetic, about on par with my '50 Bantam I had as a kid. ;) I had no hand in their set-up though, so can't comment on their mechanical condition at the time.

What amazes me though, is seeing totally incorrectly adjusted drum brakes on mega-buck restorations, regardless of marque. Seems the budget was quite OK for the 1000's for a paint job, but ran out for a new set of brake shoes/linings.:rolleyes:

piet
 
Not claiming it’s a great brake and I can’t comment on Laverda drum brakes.
A youthful poverty stricken self education of various Brit bikes left me with the impression that the name came from some hack endeavouring to write a witty piece to gain a name for themselves and every home mechanic used the name to hide their own inability to set up or their unwillingness to research how to set up one of these brakes properly.
Yes there are improvements that can be made with careful selection of alternative components and yes, best to ride within the brakes capability.
My X75 Hurricane has carried me across Europe numerous times without incident due to poor brakes.
Agreed, it does rather leave one gasping when yet another superb rebuild/restoration appears between the covers of some bike magazine only to reveal itself as being close to unrideable due to poorly set up brakes. If I can spot it then what else has been completed to a similar standard that I’ve missed.
/6 BMW front drum was the worst I’ve come across, but a campsite in a French campsite was not the best place to discover why this one was quiet so poor.
 
Very nice Steve! It's actually a lot less obtrusive than my OCD would allow.
Been comtemplating this myself but currently don't have a project I would want to fit it to... maybe the 750 flat tracker that's running around in the back of my brain. ;)
How is the lever/switchblock clearance when deployed?
piet

Flat-tracker sounds cool, looking forward to that! :)
Switchblock clearance is a little compromised by the reach adjuster, but overall where I have it I use up 205mm and a Jota bar is 210mm. Pretty sure Craig had his one fitted fine on Jota bars on his 750 before changing to Renthals same as mine.
The only slight 'issue' I've noted is that even though it includes a mirror mount, it is on the near-sdie of the bar and my mirror ended up a little too close. An adapter mounting the mirror to the clamp bolt or a separate mirror mount between clutch mech and switchblock would be better, if a little messy.
1707605664849.png

Just stick the lever a couple of minutes, literally in caustic soda and it'll come out nice and shiny.
Paul
With the adjuster it's a few different pieces, with some steel there I think. Would need disassembly before either blasting or stripping, most likely why it's still black now! :)

The Magura system is listed as either black or silver on the website I get. Not available in Norway anyway from the accessory joints (out of stock, none planned) so it would be the big import tax bonus for the collectors.
I got mine from ebay US, paid the significant freight, paid the AU GST automatically applied. Still under au$500 even with a shitty exchange rate IIRC. As I mentioned, it's not cheap, but I very much doubt the alternatives would be less. And you're in Norway, richest country in the world, reinvesting it's natural resources winfall into it's people instead of giving it for free to a couple of billionaires. Stop whingeing. :D
 
I believe that there is an alternative to the Majura setup manufactured in Taiwan by a company called Frando. Have a look at there motorcycle specific brake and clutch products, pretty impressive stuff and reputably good quality.
Tom
 
Hi @Laverdalothar ,
The kit I used was part number 2100309 to suit 2010-16 Kawa Z1000. Here's one:
The hose length was fine for my Jota with Renthal 'flat' one piece bars, I expect it would also be fine for stock jota bars for anyone unfortunate enough to still use those. :) Really high bars might require a longer hose, perhaps there is a suitable alternative kit. Note the lever comes in silver or black, silver looks better on the old clunkers, so be sure any alternative number you get has the silver lever.
I copied the esteemed @CJMAC who trod this path before me with his SF2. He initially fitted it with the DAM extended lever and the operation was TOO LIGHT and was unbalanced with the other controls. A return to the stock release lever makes it perfect.
As mentioned, it comes pre-bled and does not require disassembly of that to fit.
The only slight modification I made was the adapter sleeve shown here:
View attachment 88056
The shiny silver bit is a separate tophat shaped piece to adapt the slave cylinder to various bikes. The hole in the Laverda crankcase is M8x1.0, so the through diameter is ~7mm. The sleeve that came with the kit is 8mm outside diameter, so I turned it down to 7mm. It's a bit iffy because the inside diameter of that sleeve is 6mm from memory, so only 0.5mm wall thickness. In reality, all it does is centralise the slave cylinder and hold it a bit more securely, you could probably do without it altogether. Maybe then the stroke might not quite work, in which case put a few 8mm washers over it to match the thickness of the step in the tophat piece. The best option might be an M8x1.0 bolt drilled to 6mm thru and the head turned down to just a couple of mm thick like the adapter sleeve, but it's really not necessary. The cylinder is stabilised by the internal spring which exerts a slight pressure on the release system.
It's a brilliant bit of kit that just works, is easy to fit, requires no mods to the bike, is mineral oil based so does not absorb water, is away from the front sprocket so does not absorb chain grease and dirt into the hydraulics.
The kit is perhaps a bit pricey, but it's probably competitive or cheaper than the alternatives and retains the look of the original cover.
Can you tell I like it? :LOL:

Cheers
SteveB

(Post edited to correct diameters above)
Perfect, Steve, thanks a lot!!! This is something to be put into the Wiki-section I would say so it can be found easier in the future! If you don't mind, I'll make a PDF out of it and ask the admins to get it on there.
 
Perfect, Steve, thanks a lot!!! This is something to be put into the Wiki-section I would say so it can be found easier in the future! If you don't mind, I'll make a PDF out of it and ask the admins to get it on there.
You should be able to add it yourself, Lothar. Or at least, that's how I hope the user permissions are set! 🤞
 
Magura hymec is another excellent option. I put one on the Jota and it's brilliant. Don't need to remove the sprocket cover, even comes pre-bled, just fit and enjoy a nice light and friction-free clutch. Both master and slave cylinders are very small and hardly noticeable.

View attachment 88044
This is the official document by Magura, you can order a system for Laverda:
 

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This is the official document by Magura, you can order a system for Laverda:
That's brilliant to know! (y) Is there any reference number or similar?
It would be good to have the exact specifications to cook up the ideal system and document it as Lothar has suggested.
From a Hymec catalogue, the system I used (code 2 100 309) used master type 167 Black, piston dia 10.5 (is that master or slave?), slave cylinder type 0120655, 'assembly' 53 (??), and 'length' (presumably the hose) 1045mm. Most of it seemed pretty perfect other than the M8x1 mounting and preferring a silver lever.

hymec data.png
 
Just incase anyone didn't believe that a 750 clutch could be too light.
And as Steve mentioned, I took the 'DAM extension arm' off to bring it back to useable after this video.
I machined up a nice little perch for the choke.
And as Paul has mentioned, I caustic etched off the black anodize but it did require a fair bit of polishing to get it presentable.

View attachment VID_20211113_095120.mp4
 
So that's with a long lever arm at the motor AND a hydro system. Then I can understand too light - otherwise I'd say the clutch springs are too light or there's so little travel at the pushrod you wouldn't be able top ride it.
 
So that's with a long lever arm at the motor AND a hydro system. Then I can understand too light - otherwise I'd say the clutch springs are too light or there's so little travel at the pushrod you wouldn't be able top ride it.
Now I remember......
That is with the clutch springs out of Steve's race bike.
The travel was a tiny bit limited and it was hard to find neutral at the lights. Removing the long arm balanced it up perfectly
 
Yes, it's possible to go too light, there is no free lunch in Physics. So it's either an extended lever but not too extended or the correct hydro master size, BTW its geometry also has an effect, Radial Masters produce a lighter action than std square action ones. The purch and lever also come into it, It is impossible to extend my Pantah lower lever, it is just as bad but its fix was an Aprilia purch and dogleg lever with better gyomatry, not as good as my 3c but at least bearable My first extended arm was one I made, I read in Classic Bike that Phil Todd had done it so I made my own. I had no idea what length he used so I made my own and urred on as long as possible but that made getting neutral at rest impossible so I rang him from Oz and asked about buying a kit. I had struggled for a good year braking cables and ending up with constant wrist pain. I had tried a gadget, but that was way too complicated and I broke its cable as well. Phil's kit was a game-changer for me. I have no idea why some bikes are ok and mine was a nightmare, maybe it's in its hand-built tolerances, who the hell knows? BTW I am 120kg and spent my life doing hard labour in the building industry so I am not exactly a wallflower strength-wise.
 
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